What are the Causes of Hearing Loss in Older People?
As is the case with other types of auditory impairment and regardless of what may be the underlying causes, hearing loss in older people, described under the catchall title of presbycusis, will involve either the ear’s conductive or its sensory abilities and, quite commonly, both of these functions will be affected to varying degrees. One specific causative condition that is encountered quite commonly among elderly subjects and one that that can result in an interruption to the continuity of the ear’s conductive pathway, is a degenerative process known as otosclerosis.
In normal bone metabolism, two types of specialised cells are present and constantly active and both of these are essential to the continued health of this tough connective tissue. The osteoblasts generate new tissue that is later broken down by the osteoclasts in an ongoing process of remodelling that serves to keep the bone tissue functioning optimally. In otosclerosis this remodelling process becomes faulty and abnormal tissue is produced. Since the condition affects the small bones in the middle ear that are known as ossicles, these will in time become fused and so, in parallel, will lose their ability to transmit sounds. This results in a form of conductive deafness that normally affects both ears. Though mild at first it is progressive and sufferers will require an efficient hearing aid.
What may also be among the more common causes of hearing loss in older people is the gradual deterioration of the delicate hair-like cells that line the inside of the cochlea; a snail-shaped organ that is located in the innermost chamber of the ear. It is these highly specialised cells that act as the receptors for the vibrations created by incoming sounds received via the outer and middle ear. In response to these mechanical stimuli, they are able to generate a range of small electrical impulses for onward transmission to the brain where they are interpreted as specific sounds. Because of their high degree of differentiation, the body is unable to repair or to replace these specialised cells once they have become damaged and some degree of permanent and possibly progressive sensorineural deafness will be the inevitable consequence.
In practice, auditory function will begin a slow deterioration in most subjects from around the third decade of life. Though the decline may be detectable by sensitive audiology equipment, its symptoms can often take several more decades before they become evident to the subject.
Not all of the causes of hearing loss in older people are a natural feature of aging, however. Our lifestyles too may play a significant role in determining auditory efficiency. It has long been established, for instance, that the incidence of presbycusis is significantly higher in subjects who smoke when compared with its frequency among non-smokers. Though perhaps not as alarming as other potential consequences of tobacco use, it could certainly be food for thought for anyone whose lifestyle may be dependent upon above average auditory acuity.
Noise is among the most significant contributors to deafness. A lifetime in a factory without protection has left many profoundly deaf, but the loud music from stereos and iPods, especially when delivered via in-ear headphones, has seen what commonly causes hearing loss in older people now affecting the nation’s youth also. You would have to agree that the latter is a worrisome fact, if anything.